<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>

</body>
<script>
    var str = '';
    for (var i = 1; i <= 5; i++) {
        for (var j = 1; j <= 5; j++) {
            str = str + '⭐'
        }
        str = str + '\n'
    }
    console.log(str);
</script>

</html>